Flood Extent Mapping
Extract flood extent from SAR backscatter imagery.
CLI Usage
# Local file mode (backward compatible)
python scripts/flood_extent_mapping.py --sar sar.tif
python scripts/flood_extent_mapping.py --sar sar.tif --threshold -16
python scripts/flood_extent_mapping.py --sar sar.tif --output-dir my_output
# Auto-download mode — fetch Sentinel-1 GRD from Microsoft Planetary Computer
# (no API key required; one scene per invocation)
python scripts/flood_extent_mapping.py \
--bbox 116,39,117,40 \
--date-range 2024-06-01,2024-06-30 \
--output-dir my_output
Data Download
When --bbox (or --aoi-file) and --date-range are provided, the skill
auto-downloads one Sentinel-1 GRD scene from the Microsoft Planetary
Computer STAC catalog (collection sentinel-1-grd). The downloaded file
is written to <output_dir>/downloaded/ and the SAR analysis runs on it
exactly as if a local file had been passed via --sar.
The output-manifest.json records data_source, collection, bbox,
date_range, and fetched_at whenever auto-download is used.
Parameters
| Argument | Required | Default | Description |
|---|---|---|---|
--sar |
One-of | — | Path to local SAR backscatter raster (dB, calibrated) |
--bbox |
One-of | — | W,S,E,N in WGS-84; triggers auto-download |
--date-range |
w/ bbox | — | START,END ISO-8601; triggers auto-download |
--aoi-file |
No | — | GeoJSON Polygon / MultiPolygon (alternative to --bbox) |
--threshold |
No | -15 |
Water threshold in dB |
--output-dir, -o |
No | flood-output |
Directory to write outputs |
--synthetic |
No | off | Use synthetic demo data (no real inputs) |
Output
| File | Description |
|---|---|
flood-report.json |
Machine-readable flood extent stats (water area, depth proxy) |
report.html |
Human-readable HTML report |
output-manifest.json |
Run metadata + result summary |
Exit Codes
| Code | Meaning |
|---|---|
| 0 | Success |
| 2 | Argument error |
| 7 | Processing failure |